Sung-Doo Kim

Randomized Trial of Myeloablative Conditioning Regimens: Busulfan Plus Cyclophosphamide Versus Busulfan Plus Fludarabine

PURPOSE We conducted a phase III randomized clinical trial to compare two myeloablative conditioning regimens for allogeneic hematopoietic cell transplantation (HCT) in patients with leukemia and myelodysplastic syndrome. PATIENTS AND METHODS After randomization, 64 patients received busulfan (3.2 mg/kg per day × 4 days) plus cyclophosphamide (60 mg/kg per day × 2 days; BuCy), and 62 patients received busulfan (same dose and schedule) plus fludarabine (30 mg/m(2) per day × 5 days; BuFlu). RESULTS The median age was 41 years (range, 17 to 59 years). Five patients in the BuFlu arm experienced graft failure (primary, n = 1; secondary, n = 4). At 4 weeks after HCT, the median percentage of recipient hematopoietic chimerism was significantly greater in the BuFlu arm (0% v 5.5%; P < .001), and complete donor chimerism was greater in the BuCy arm (97.2% v 44.4%; P < .001). Severe (grade 3 or higher) infection and gastrointestinal adverse events were significantly more common in the BuCy arm, but the frequencies of hepatic adverse events were similar in the two arms. Nonrelapse mortality was similar in the two arms, but the BuCy arm had better overall survival (OS), relapse-free survival (RFS), and event-free survival (EFS; OS at 2 years, 67.4% v 41.4%, P = .014; RFS, 74.7% v 54.9%, P = .027; EFS, 60.7% v 36.0%, P = .014). CONCLUSION Our results indicate that the BuFlu regimen is not a suitable replacement for the BuCy regimen in young adults who are eligible for myeloablative conditioning therapy for allogeneic HCT.

Nilotinib combined with multiagent chemotherapy for newly diagnosed Philadelphia-positive acute lymphoblastic leukemia

We investigated the effects of nilotinib plus multiagent chemotherapy, followed by consolidation/maintenance or allogeneic hematopoietic cell transplantation (allo-HCT) for adult patients with newly diagnosed Philadelphia-positive (Ph-pos) acute lymphoblastic leukemia (ALL). Study subjects received induction treatment that comprised concurrent vincristine, daunorubicin, prednisolone, and nilotinib. After achieving complete hematologic remission (HCR), subjects received either 5 courses of consolidation, followed by 2-year maintenance with nilotinib, or allo-HCT. Minimal residual disease (MRD) was assessed at HCR, and every 3 months thereafter. The molecular responses (MRs) were defined as MR3 for BCR-ABL1/G6PDH ratios ≤10(-3) and MR5 for ratios <10(-5). Ninety evaluable subjects, ages 17 to 71 years, were enrolled in 17 centers. The HCR rate was 91%; 57 subjects received allo-HCT. The cumulative MR5 rate was 94%; the 2-year hematologic relapse-free survival (HRFS) rate was 72% for 82 subjects that achieved HCR, and the 2-year overall survival rate was 72%. Subjects that failed to achieve MR3 or MR5 were 9.1 times (P = .004) or 6.3 times (P = .001) more prone to hematologic relapse, respectively, than those that achieved MR3 or MR5. MRD statuses just before allo-HCT and at 3 months after allo-HCT were predictive of 2-year HRFS. Adverse events occurred mainly during induction, and most were reversible with dose reduction or transient interruption of nilotinib. The combination of nilotinib with high-dose cytotoxic drugs was feasible, and it effectively achieved high cumulative complete molecular remission and HRFS rates. The MRD status at early postremission time was predictive of the HRFS. This trial was registered at www.clinicaltrials.gov as #NCT00844298.

Influence of GST gene polymorphisms on the clearance of intravenous busulfan in adult patients undergoing hematopoietic cell transplantation.

Intravenous (i.v.) busulfan can produce a more consistent pharmacokinetic profile than oral formulations can, but nonetheless, significant interpatient variability is evident. We investigated the influence of polymorphisms of 3 GST isozyme genes (GSTA1, GSTM1, and GSTT1) on i.v. busulfan clearance. Fifty-eight adult patients who received 3.2 mg/kg/day of busulfan as conditioning for hematopoietic cell transplantation were included in this study. Stepwise multiple linear regression demonstrated that GSTA1 variant GSTA1∗B (P = .004), GSTM1/GSTT1 double-null genotype (P = .039), and actual body weight (P = .001) were significantly associated with lower clearance of i.v. busulfan. A trend test analyzing the overall effect of GST genotype on busulfan pharmacokinetics, combining GSTA1 gene polymorphism and the number of GSTM1- and GSTT-null genotypes, showed a significant correlation between GST genotype and busulfan clearance (P = .001). The clearance of i.v. busulfan was similar between patients with GSTA1∗A/∗A and GSTM1/GSTT1 double-null genotypes and those with GSTA1∗A/∗B and GSTM1/GSTT1 double-positive genotypes. In conclusion, a pharmacogenetic approach using GST gene polymorphisms may be valuable in optimizing the i.v. busulfan dosage scheme. Our results also highlight the importance of including polygenic analyses and addressing interactions among isozyme genes in pharmacogenetic studies.

Decreased incidence of febrile episodes with antibiotic prophylaxis in the treatment of decitabine for myelodysplastic syndrome

We analyzed the role of antibiotic prophylaxis during decitabine treatment for MDS. The primary endpoint was the incidence of febrile episodes. The total number of decitabine cycles given to 28 patients was 131, and febrile episodes occurred in 15 cycles (11.5%). Antibiotic prophylaxis was orally administered in 95 cycles (72.5%). Febrile episodes were significantly less frequent among patients who received antibiotic prophylaxis (7.4%) than in those without prophylaxis (22.2%) (P=0.017). In conclusion, antibiotic prophylaxis reduced the incidence of febrile episodes in patients who received decitabine treatment for MDS, especially at earlier cycles and in the presence of severe cytopenia.

Single nucleotide polymorphism of Wilms’ tumor 1 gene rs16754 in Korean patients with cytogenetically normal acute myeloid leukemia

A recent study from Germany showed that WT1 single nucleotide polymorphism (SNP) rs16754 was an independent prognostic factor in cytogenetically normal acute myeloid leukemia (CN-AML). We analyzed clinical impact of the WT1 rs16754 genotype on disease characteristics and outcomes in Korean patients with CN-AML. A total of 73 patients with CN-AML were included in the study. All patients received standard induction chemotherapy and their bone marrow or peripheral blood samples were cryopreserved at the time of diagnosis. WT1 exons 7 and 9 were amplified using polymerase chain reaction and directly sequenced. The genotype frequency for WT1 rs16754 was 6.8% for AA, 39.7% for GA, and 53.4% for GG. G was a minor allele in German population, whereas it was a major allele in Korean (13.7% vs. 73.3%, P < 0.001). Complete remission was induced in 85.3% of patients with GA/AA and 84.6% of those with GG (P = 0.936). Survival rates were also similar between patients with GG and those with GA/AA. Asian and Western populations exhibited significant differences in allele and genotype frequencies of WT1 rs16754. In Korean patients with CN-AML, WT1 SNP rs16754 had no significant impact on clinical outcomes and further investigations are needed to define prognostic implication of WT1 SNP rs16754 in CN-AML.

Allogeneic hematopoietic cell transplantation in adult patients with myelodysplastic/myeloproliferative neoplasms

Background In adults, the 2 main types of myelodysplastic/myeloproliferative neoplasms (MDS/MPN) are chronic myelomonocytic leukemia (CMML) and atypical chronic myeloid leukemia (aCML). Both are associated with a poor prognosis. Allogeneic hematopoietic cell transplantation (HCT) is the only known curative treatment modality for these diseases, but data on outcomes following such treatment are limited. We analyzed the outcomes of patients with MDS/MPN after allogeneic HCT. Methods This retrospective study included 10 patients with MDS/MPN who received allogeneic HCT at Asan Medical Center from 2002 to 2010. Of these 10 patients, 7 had CMML, 2 had aCML, and 1 had unclassifiable MDS/MPN. Five patients received a myeloablative conditioning (MAC) regimen (busulfan-cyclophosphamide), and 5 received reduced-intensity conditioning (RIC) regimen. Results Neutrophil engraftment was achieved in all patients. After a median follow-up of 47.5 months among surviving patients, 4 had relapsed and 5 had died. There was only 1 treatment-related death. The 5-year rates of overall, relapse-free, and event-free survival were 42.2%, 51.9%, and 46.7%, respectively. Relapse was the leading cause of treatment failure, and all relapses were observed in patients who had received RIC and who did not develop chronic graft-versus-host disease. Conclusion Allogeneic HCT can induce durable remission in patients with MDS/MPN, but RIC cannot replace MAC in patients eligible for myeloablative treatments.

Clinical outcome after failure of hypomethylating therapy for myelodysplastic syndrome.

Around half of patients with myelodysplastic syndrome (MDS) fail to respond to hypomethylating therapy (HMT) and most responders progress within 2 yr. Retrospective studies report poor outcomes after HMT failure. Here, we analyzed the outcomes of patients suffering HMT failure. Of 149 patients with MDS treated with either azacitidine or decitabine, 91 who experienced HMT failure were included in the study. Median overall survival (OS) was 12.1 months: 16.2 months for lower‐risk MDS and 9.3 months for higher‐risk MDS. Disease status and progression to acute myeloid leukemia (AML) at the time of HMT failure were independent prognostic factors for OS. Fifty‐four patients received one or more treatment modalities, and 23 received allogeneic hematopoietic cell transplantation (HCT). The objective response to non‐transplant treatments was poor (11–17%), whereas 17 transplanted patients showed a complete response. OS probability at 2 yr post‐HCT was 60.9%: 78.6% for patients receiving HCT during MDS and 33.3% for those receiving HCT after developing AML. In conclusion, the clinical outcome of patients after HMT failure was poor. Long‐term disease‐free survival was observed in approximately 50% of patients who received allogeneic HCT. Therefore, allogeneic HCT should be performed early in appropriate patients, and particularly before progression to AML.

Two cycles of the PS-341/bortezomib, adriamycin, and dexamethasone combination followed by autologous hematopoietic cell transplantation in newly diagnosed multiple myeloma patients

Introduction:  Treatment with 3–6 cycles of PS‐341/bortezomib, adriamycin, and dexamethasone (PAD) has been explored in terms of induction therapy prior to autologous stem cell transplantation (ASCT) in patients with multiple myeloma (MM). We evaluated the effects of two cycles of PAD given before ASCT.

Pre-engraftment graft-versus-host disease after allogeneic hematopoietic cell transplantation for acute leukemia

Objectives:  Acute graft‐versus‐host disease (GVHD) usually occurs with neutrophil engraftment following allogeneic hematopoietic cell transplantation (HCT), but it can also occur before engraftment. We intended to analyze the effects of timing of acute GVHD on leukemia relapse and mortality.

A prediction model for complete remission upon reinduction for patients with acute myeloid leukemia after failure of anthracycline and cytarabine standard chemotherapy

The aim of this study was to investigate clinical parameters that might predict complete remission (CR) following reinduction therapy in patients with acute myeloid leukemia (AML). We retrospectively analyzed outcomes in 142 patients who failed to achieve CR with standard anthracycline-plus-cytarabine induction chemotherapy (IND1) and who received the same regimen as a reduction therapy (IND2). The CR rate after reinduction was 54%. Multivariate analysis showed that the presence of peripheral blood (PB) blasts on the day of commencement of IND2 and ≥20% blasts in an interim BM sample taken during IND1 (C1-INT-BM) were independent risk factors for failure of remission. Our scoring system for prediction of CR after reinduction (CRAR score) included a favorable chromosome risk group, absence of PB blasts on the day of commencement of IND2, and ≤21% blasts in the C1-INT-BM. This scoring system predicted that the rates of CR in the four subgroups would be 92.1%, 68.9%, 29.5%, and 7.3%, respectively, in good agreement with observed CR rates. The CRAR scoring model might be associated with the possibility of achieving CR after reinduction, and may be helpful in choosing alternative strategy for AML patients refractory to standard induction chemotherapy, although further prospective validation is required.